The activation heat treatment of an SiC substrate after ion implantation requires a temperature from 1600 to 1900° C. It is also required to perform the activation heat treatment in a short period of time in order to activate impurities without imparting time for atoms to move. It is further required to reduce variations in the in-plaine temperature distribution of the SiC substrate being heat treated as well as to provide improved mass productivity.
In response to such a demand, a heat treatment apparatus has been suggested in which a substrate was retained in a tube-shaped body formed of a high melting point material, and the tube-shaped body was heated with an RF coil at a high frequency to thereby create a high-temperature region in the tube-shaped body (Patent Literature 1). The heat treatment apparatus provides a temperature rise rate of about 20 to 30° C. per minute which is two to three times that provided by heating using a conventional infrared lamp, thereby reducing variations in the in-plane temperature distribution.